Positive electrode material, preparation method and uses thereof
The present application relates to the electrochemical field, and in particular, to a positive electrode material, and an electrochemical energy storage apparatus having thereof. The present application provides a positive electrode material, including a substrate. The substrate includes secondary particles containing primary particles. A surface of the substrate is coated with an oxide coating layer. The oxide coating layer comprises a coating element, and the coating element is selected from one or more of Al, Ba, Zn, Ti, Zr, Mg, W, Y, Si, Sn, B, Co, or P. The electrochemical energy storage apparatus comprises the foregoing positive electrode material.
1. A positive electrode material, comprising a substrate, wherein the substrate comprises secondary particles containing primary particles, a molecular formula of the substrate is Li x Ni y Co z M k Me p O r A m , 0.95≤x≤1.05, 0.50≤y≤0.98, 0≤z≤0.3, 0≤k≤0.4, 0≤p≤0.05, 1≤r≤2, 0≤m≤2, m+r≤2, M is Mn and/or Al, Me is selected from one or more of Zr, Zn, Cu, Cr, Mg, Fe, V, Ti, Sr, Sb, Y, W, Nb, or Al, and A is selected from one or more of F, Cl, or Br;
a surface of the substrate is coated with an oxide coating layer, and the oxide coating layer comprises a coating element, and the coating element is selected from one or more of Al, Ba, Zn, Ti, Zr, Mg, W, Y, Si, Sn, B, Co, or P;
a powder resistivity p of the positive electrode material under a 12 MPa pressure is 10 Ω*cm-5,000 Ω*cm, more specifically 10 Ω*cm-2,000 Ω*cm;
a content Mv of the coating element per unit volume of the positive electrode material is 400 μg/cm 3 to 15,000 μg/cm 3 ; and
the powder resistivity ρ and the content Mv of the coating element satisfy: ρ/Mv≤1 Ω*cm 4 /μg.
2. The positive electrode material according to claim 1 , wherein the content Mv of the coating element 800 μg/cm 3 to 10,000μ/cm 3 .
3. The positive electrode material according to claim 1 , wherein the powder resistivity ρ and the content Mv of the coating element satisfy: ρ/Mv≤0.5 Ω*cm 4 /μg.
4. The positive electrode material according to claim 1 , wherein the coating element is selected from at least two or more of Al, Ba, Zn, Ti, W, Y, Si, Sn, B, Co, or P.
5. The positive electrode material according to claim 1 , wherein the coating element is distributed on a surface of at least a part of the primary particles inside the secondary particles; and/or
the coating element is distributed at grain boundaries between adjacent primary particles.
6. The positive electrode material according to claim 5 , wherein a content of the coating element in the oxide coating layer is 60 wt % or more of a total content of the coating element in the positive electrode active material; more specifically, the content of the coating element in the oxide coating layer is 80 wt %-98 wt % of the total content of the coating element in the positive electrode active material.
7. The positive electrode material according to claim 1 , wherein in the molecular formula of the substrate, 0.80≤y≤0.98, 0≤z≤0.1, 0≤k≤0.1, and 0≤p≤0.03.
8. The positive electrode material according to claim 1 , wherein Dv50 of the secondary particles is 5 μm-18 μm, and a particle diameter range of the primary particles is 0.1 μm-1 μm; more specifically, Dv50 of the secondary particles is 8 μm-15 μm, and the particle diameter range of the primary particles is 0.2 μm-0.8 μm.
9. The positive electrode material according to claim 1 , wherein a specific surface area of the positive electrode material is 0.1 m 2 /g-0.8 m 2 /g.
10. The positive electrode material according to claim 1 , wherein a content of Li 2 CO 3 in residual lithium on a surface of the positive electrode material is less than 3,000 ppm, and a content of LiOH in the residual lithium on the surface of the positive electrode material is less than 5,000 ppm.
11. The positive electrode material according to claim 10 , wherein in the residual lithium on the surface of the positive electrode material, the content of Li 2 CO 3 is less than the content of LiOH.
12. An electrochemical energy storage apparatus, comprising a positive electrode material, wherein
the positive electrode material comprises a substrate, and the substrate comprises secondary particles containing primary particles, a molecular formula of the substrate is Li x Ni y Co z M k Me p O r A m , 0.95≤x≤1.05, 0.50≤y≤0.98, 0≤z≤0.3, 0≤k≤0.4, 0≤p≤0.05, 1≤r≤2, 0≤m≤2, m+r≤2, M is Mn and/or Al, Me is selected from one or more of Zr, Zn, Cu, Cr, Mg, Fe, V, Ti, Sr, Sb, Y, W, Nb, or Al, and A is selected from one or more of F, Cl, or Br;
a surface of the substrate is coated with an oxide coating layer, and the oxide coating layer comprises a coating element, and the coating element is selected from one or more of Al, Ba, Zn, Ti, Zr, Mg, W, Y, Si, Sn, B, Co, or P;
a powder resistivity p of the positive electrode material under a 12 MPa pressure is 10 Ω*cm-5,000 Ω*cm, more specifically 10 Ω*cm-2,000 Ω*cm;
a content Mv of the coating element per unit volume of the positive electrode material is 400 μm/cm 3 to 15,000 μm/cm 3 ; and
the powder resistivity ρ and the content Mv of the coating element satisfy: ρ/Mv≤1 Ω*cm 4 /μg.
13. The electrochemical energy storage apparatus according to claim 12 , wherein the content Mv of the coating element is 800 μm/cm 3 to 10,000 μg/cm 3 .
14. The electrochemical energy storage apparatus according to claim 12 , wherein the powder resistivity ρ and the content Mv of the coating element satisfy: ρ/Mv≤0.5 Ω*cm 4 /μg.
15. The electrochemical energy storage apparatus according to claim 12 , wherein the coating element is selected from at least two or more of Al, Ba, Zn, Ti, W, Y, Si, Sn, B, Co, or P.
16. The electrochemical energy storage apparatus according to claim 12 , wherein the coating element is distributed on a surface of at least a part of the primary particles inside the secondary particles; and/or
the coating element is distributed at grain boundaries between adjacent primary particles.
17. The electrochemical energy storage apparatus according to claim 12 , wherein in the molecular formula of the substrate, 0.80≤y≤0.98, 0≤z≤0.1, 0≤k≤0.1, and 0≤p≤0.03.
18. The electrochemical energy storage apparatus according to claim 12 , wherein Dv50 of the secondary particles is 5 μm-18 μm, and a particle diameter range of the primary particles is 0.1 μm-1 μm; more specifically, Dv50 of the secondary particles is 8 μm-15 μm, and the particle diameter range of the primary particles is 0.2 μm-0.8 μm.
19. The electrochemical energy storage apparatus according to claim 12 , wherein a specific surface area of the positive electrode material is 0.1 m 2 /g-0.8 m 2 /g.
20. The electrochemical energy storage apparatus according to claim 12 , wherein a content of Li 2 CO 3 in residual lithium on a surface of the positive electrode material is less than 3,000 ppm, and a content of LiOH in the residual lithium on the surface of the positive electrode material is less than 5,000 ppm.